Smoke point lamp and chimney



1958 x R; A. HUNT, JR, ETAL 2,819,607

SMOKE POINT LAMP AND CHIMNEY- Filed Sept. 2'7, 1955 h 4 sheets -sheet 1 [23a H l Fig. 1 Russell A. Hunt, Jr.

Frederick It Rakovsky INVENTORS.

ATTORNEY Jan. 14, 1958 R. A. HUNT, JR., ET AL 2,819,607

SMOKE POINT LAMP AND CHIMNEY Filed. Sept. 27. 1956 4 Sheets-Sheet 2 t I 11 II I 2a /3-" g1}. I I

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f I IL Russell A. Hunt, Jr. Frederick ll Rakank INVENTO /0 BY 1 M09 ATTORNEY Jan. 14, 1958 R. HUNT, JR., ETAL SMOKE POINT LAMP AND CHIMNEY 4 Sheets-Sheet 5 Filed Sept. 27, 1956 w w w A m 4 w m w W w /o M M ./.\D m 1A1. mwmwwwwmwwmwmm N E 55mm Mksm Russell A. Hunt Jr. Frederick M Evian/(y INVENTORS.

A TTURNE'Y Jan. 14, 1958 R. A. HUNT, JR., ETAL 2,819,507

SMOKE POINT LAMP AND CHIMNEY Filed Sept. 27, 1956 4 Sheets-Sheet 4 Russell-A. Hum; Jr. Frederick W Rakqwsky ATTORNEY United States SMOKE POINT LAMP AND CHIMNEY Application September 27, 1956, Serial No. 612,384

6 Claims. (Cl. 73--36) This invention relates to an apparatus for determining smoke point of hydrocarbon fuels.

One of the many control tests used in the petroleum industry to maintain a uniform quality of product is the smoke point test in which a small quantity of the fuel to be tested is burned in a specified test lamp in which the flame height can be adjusted. The smoke point is defined as the height in millimeters of the highest flame produced without smoking. The higher the smoke point the better the fuel burning quality and the lower the sooting tendency. Thus, smoke point is used to define minimum acceptable burning quality and it is of particular importance that the lamp used provide maximum sensitivity in the range where minimum quality requirements fall.

Smoke points have been used since about 1930 as a measurement of quality of kerosene used as an illuminating oil. More recently, smoke point has been used as a measure of fuel burning quality as, for example, the sooting tendency of heating oils and jet aircraft fuels. A standard method of test was described before the World Petroleum Congress in 1933. In such a test the atent D i lamp is lit, adjusted to give a smokeless flame, and

allowed to burn 10 minutes to reach equilibrium. The flame is then turned up until it is definitely smoking and then lowered slowly until the smokey tail just disappears. The height of the flame at this point is taken as the smoke point. A tentative ASTM test based upon this test procedure has been proposed for use on jet fuels and is designated as ASTM D 1322-54T.

Various types oflamps have been used in smoke point studies but no one of them has been entirely satisfactory from all standpoints. For example, smoke point lamps heretofore available do not permit a great enough spread in smoke points between different fuels and do not provide adequate means for minute adjustments of the wick which are necessary for the desired sensitivity and accuracy.

The increased emphasis on carbon deposition in jet engines has increased substantially the need for methods for specifying fuel burning quality. Smoke point is currently used in jet fuel specifications and since minimum quality is specified it is desirable to use a lamp having maximum sensitivity, in this range, and which provides a precise method of determining minimum jet fuel burning quality. However, smoke points obtained with one lamp must correlate well with those obtained with other lamps now in use.

It is, therefore, a primary object of the invention to provide a smoke point apparatus having a maximum sensitivity for indicating the greatest spread in smoke points. An additional object is to provide a lamp adapted foruse on a wide variety of fuels. A further object of the invention is to provide a lamp with an accurate means for making precise adjustments in the wick height. A further object is to provide an apparatus which is rugged and of simple construction. Still another object of the invention is to provide an apparatus which 2,819,607 Patented Jan. 14, 1958 is substantially foolproof in its operation so that it may be used by personnel without specialized technical training. Another object of our invention is to provide a chimney structure by means of which smoke point may easily be read without excluding light about the lamp. A further object is to provide a chimney which is free of multiple images. An additional object is to provide a lamp chimney which embodies scale means disposed to minimize parallax.

Another object is to provide an apparatusgiving results which can be correlated with smoke points obtained on other lamps. These and other objects of our invention will be understood from the description thereof which follows. i

Although a number of lamps have been used in smoke point studies and although test procedures have been devised using such lamps, there are not available such information and data as would permit one to design a lamp with optimum sensitivity. Consequently, we have made studies to ascertain the physical variables of lamp design which affect smoke point. The smoke lamp devised by us gives the best distinction between fuels consistent with ease of operation and adaptability for use in routine testing.

Briefly, according to our invention, we provide a lamp having a wick diameter of inch; chimney diameter 22 millimeters and chimney height of 8 inches. A wick guide height is 1 inch. Our lamp also embodies an improved mechanism for raising and lowering the wick within the wick guide and chimney.

Our chimney comprises a glass tube which is internally frosted except for a longitudinal strip running from end to end on one face of the chimney. A scale is provided on the exterior surface of the tube adjacent the clear window so that flame height may be readily determined. The internal frosting of the chimney eliminates the multiple images and excludes enough light so that smoke point may be determined under any lighting conditions.

Further details of construction and advantages of our invention will be described in conjunction with a preferred embodiment illustrated in the accompanying drawings wherein: t

Figure 1 is a perspective of the assembly;

Figure 2 is an elevation, partly in section, of the apparatus of Figure 1;

Figure 3. presents correlation data with other lamps;

Figure 4 is an elevation, partly in section, illustrating a further embodiment of the chimney, chimney support and scale;

Figure 5 is a top view of the structure in Figure 4; and

Figure 6 is a fragmentary view illustrating still another embodiment of the chimney support.

Referring to the drawings, the apparatus: comprises a base It) on which is mounted the tubular support or housing 11 containing a threaded shaft 12 and a travelling block 13. A sleeve 14 supports the cylindrical oil holder 15 closed at its upper end by the WlCk hOlClfil 16 comprising plug 17 and'the tubular extension 13 which is slideably retained by the wick guide 19. The wick 20 is movable within the wick guide 19 which is surrounded by the air stream 21 and above which is the glass chimney 22. The chimney support 23 is provided with a millimeter scale 24 for measuring the flame height. The sup port 23 includes a ring 23a which embraces the upper end of the chimney 22 and may be provided with a resilient grommet 23b resiliently engaging the chimney 22 as shown in Figures 1 and 2. The tubular housing 11 in cludes a cantilever beam 25 which in turn supports the chimney brace 23, the airscreen 21, and the wick guide 19.

The oil holder 15 and the wick holder 16 supported in movable sleeve 14 by a pin 26 auda slot 27. The sleeve ice 3 is held by clamp arm 28 and is positioned by the rotation of the threaded shaft 12 upon which the travelling block 13 rides. Thus, a wick 20 is placed in the wick holder 16 can be moved within the wick guide 19 to project a controlled distance intov the chimney 22 to adjust the flame height. The lower portion of the wick 20 is, of course, immersed in the fuel within the holder The wick guide 19 comprises a tube which may be threaded into a bore in the beam 25. The chimney 22 is of glass and the air screen 21 may suitably comprise mesh stainless steel; or equivalent perforated metal sheet screens with a height of about 1.125 inche being preferred for a chimney having a diameter of 22 mm. With such an assembly we use a wick guide 19 having a height of about 1 inch and a wick 20 having a diameter of about inch.

The threaded shaft 12 is rotated by a pair of helical gears 29 which are controlled by knob 30. In this manner, a relatively large movement of the control knob 30 is translated into a small and precise movement of the wick 20.

Referring to Figures 4, 5 and 6, the beam 25 provides a base for chimney support 36 fixed to beam 25 by bolt 37 and having a split ring 38 adapted to engage the exterior of the longer end of chimney 39. A grommet 40 may be provided to resiliently, but positively, support the chimney 39 in aligned position with respect to the screen 21 and the wick holder 19.

The chimney 39 is provided with non-reflecting surface 41 which may comprise a frosting produced, for example, by sand blasting or acid treating. A longitudinal window 42 is provided on the front face of the chimney 39 and represents approximately to degrees of the peripheral surface of the chimney 39. A scale 43 i provided at the margin of the window 42 and is calibrated to measure the distance from the top of the wick holder 19 in a manner similar to the scale 24 associated with the apparatus of Figures 1 and 2.

We also provide scale or reference marks 44, 45 and 46 on the rear wall of the chimney 39, these reference marks being placed at selected heights corresponding to desired flame height specifications as determined by our smoke point lamp. By means of these reference marks, the lamp may be operated in a go, no-go fashion there by permitting rapid smoke point determination in routine quality control. Of course, if the actual smoke points I are desired, they can be determined as described herein.

Figure 6 shows another type of chimney support 36 which includes a claw 47 and a grommet 43. This supporting structure may be inverted andsubstituted for the ring 23a in theapparatus of Figures 1 and- 2.

Many tests have been made employing our lamp. In such tests, the wick i lit and adjusted to give a smokeless flame and allowed to burn 10" minutes to reach equilibrium. The wick is then turned up until the flame is Results obtained on our lamp have been compared 0 with the Institute of Petroleum lamp, hereinafter referred to as the I. P. lamp, and the Factor lamp, both widely used heretofore in making smoke point tests to determine the relative sensitivities ofthe three lamps. Fuels with a smoke point of a wide range of'values are used in these correlations. Number 2 fuel oil components and blends were used to provide smoke points in the range of 5 to 30mm; kerosenes, jet fuels, and gasolines in the range from-30 to 611mm,; and pure hydro- 7 carbons in the range from. 6010x mm.

Correlations of the values from the I. P. and Factor lamps with those obtained with a lamp of our design are as shown in Figure 3. Our described lamp is more sensitive to fuel quality and gives greater spreads of values between fuels, the lamp constructed to our invention increasing the spread of the I. P. lamp by a factor of about 2 to l at low flame heights and as much as 4 to l at greater heights. Furthermore, our lamp has a range of from about 5 to 150 mm. whereas the range of prior lamps is much smaller, the I. P. for example not being able to determine smoke points greater than 50 mm.

This application is a continuation-in-part of our copending application Serial Number 553,922, filed December l9, 1955, issued as U. S. 2,819,606 and entitled Smoke Point Apparatus.

Although our invention has been described with reference to a preferred embodiment thereof, this is by way of illustration only. Accordingly, it is contemplated that modifications can be made in the apparatus and the mode of using the apparatus without departing from the scope of our invention.

What we claim is:

1. In an improved chimney for use on a smoke point lamp which lamp includes a chimney means, a wick guide means and a scale for determining flame height above said wick guide means, the improvement which comprises a tubular chimney having a major portion of its internal surface non-reflecting and a minor portion transparent to permit viewing the flame without producing multiple images and without excluding external light.

2. In a smoke point lamp including a chimney means, a wick guide means, an oil reservoir and a wick assembly associated with said reservoir and said guide means, the improved chimney means which comprises a glass tube, an internal non-reflecting surface over a major portion of the internal surface of said tube, a longitudinal window free of such surface extending substantially the length of said chimney, a scale adjacent said window and calibrated to measure the distance from the top of said wick guide means, and a support for said chimney, said support including a tube-securing means adapted to engage the said tube.

3. The apparatus of claim 2 wherein said chimney includes a reference mark within said chimney viewable through said window for determining whether a given smoke point meets a selected specification represented by said reference mark.

4. The apparatus of claim 2whereinsaid chimney support includes an upstanding arm carrying a split ring adapted to encircle the lower end 'of said chimney tube, and a resilient grommet means within said ring and con tacting the outer surface of said tube.

5. The apparatus of claim 2 wherein said tube-securing means is adapted to engage the said tube at the lower end thereof and comprises a claw.

6. A chimney for use in determining flame height of a wick-type lamp which comprises an elongated tubular member, a clear window extending substantially the entire length of said elongated tubular member, the internal surface of said tubular member except for said window being provided with a light-absorbing surface, a scale for determining the height of the flame above a reference point below said chimney, said scale being adjacent to and in alignment with said window, wherebyfiame heights may be readily determined with a minimum of parallax and without excluding light about the chimney.

References Cited in the file of this patent UNITED STATES PATENTS Armstrong u Nov..24, 1942 White Ian. 5, 1954 OTHER REFERENCES 

